Creating Clean Air Spaces During Wildland Fire Smoke Episodes: Web Summit Summary

Abstract

Effective strategies to reduce indoor air pollutant concentrations during wildfire smoke events are critically needed. Worldwide, communities in areas prone to wildfires may suffer from annual smoke exposure events lasting from days to weeks. In addition, there are many areas of the world where high pollution events are common and where methods employed to reduce exposure to pollution may have relevance to wildfire smoke pollution episodes and vice versa. This article summarizes a recent virtual meeting held by the United States Environmental Protection Agency (EPA) to share research, experiences, and other information that can inform best practices for creating clean air spaces during wildland fire smoke events. The meeting included presentations on the public health impacts of wildland fire smoke; public health agencies' experiences and resilience efforts; and methods to improve indoor air quality, including the effectiveness of air filtration methods [e.g., building heating ventilation and air conditioning (HVAC) systems and portable, free-standing air filtration systems]. These presentations and related research indicate that filtration has been demonstrated to effectively improve indoor air quality during high ambient air pollution events; however, several research questions remain regarding the longevity and maintenance of filtration equipment during and after smoke events, effects on the pollution mixture, and degree to which adverse health effects are reduced.

Development and application of a United States-wide correction for PM<sub>2.5</sub> data collected with the PurpleAir sensor

“…A nonlinear RH model was tested by adding an RH 2 / (1 − RH) term (see Eq. 3) similar to what has been used in past work for Plantower sensors and other light scattering measurements (Tryner et al, 2020a;Malings et al, 2020;Chakrabarti et al, 2004;Zheng et al, 2018;Zhang et al, 1994;Day and Malm, 2001;Soneja et al, 2014;Lal et al, 2020;Barkjohn et al, 2021). In Eq.…”

“…Air sensors are potentially of the greatest use during wildland-fire-smoke-impacted times (Holm et al, 2020;Durkin et al, 2020;Holder et al, 2020;Delp and Singer, 2020;Davison et al, 2021). A recent paper developed a smoke-specific correction (0.51 × PA cf_1 − 3.21) for PM 2.5 concentrations from PurpleAir sensors based on smoke impacts from multiple types of fires in the US (Holder et al, 2020).…”

“…The Teledyne T640 and T640x and Grimm EDM 180 are optically based monitors that have been approved as FEMs in the past decade (U.S. EPA, 2021). Humidity tends to induce large errors in these types of measurements (Chakrabarti et al, 2004;Day and Malm, 2001), which is addressed using a dryer or humidity control in FEMs (U.S. EPA, 2021). The PurpleAir sensor provides minimal humidity control due to the higher internal temperature caused by the small volume containing the electronics.…”

Using Low-Cost Sensors to Assess Fine Particulate Matter Infiltration (PM2.5) during a Wildfire Smoke Episode at a Large Inpatient Healthcare Facility

“…Most people in North America spend at least 85% of their time inside a home or other building [ 8 ], meaning that most health effects associated with ambient smoke are due to exposures that occur indoors. As wildfire seasons are expected become longer and more intense [ 9 ], it is critical that we study smoke infiltration and effective interventions, particularly in settings that house susceptible populations [ 10 ].…”

Can commercial buildings cope with Australian bushfires? An IAQ analysis

“…Commercial buildings are more likely to rely on mechanical ventilation, offering the potential to prevent pollutants' infiltration. A strategy that can be adopted is to apply positive pressurisation of the indoors by increasing air intake above the exhaust and, hence, reducing infiltration for the outdoors (Davison et al 2021). However, this may not be possible in all cases, increasing the reliance on filters.…”